Automatic stoker



I(No Model.)

A 4.Sheets -Sheet 1. AI AUTOMATIC STOKEB..

,888. Patented Nov. 12, 1895.

W/TNESSES:

AN DREW E.GRAHM. FNUTO-UTHQWASHINGTON. DE

(No Model.) 4 Sheets-Sheet 2. A. BOX.

AUTOMATIC STOKEB..

Rw 9 OO -I 1|. .:l .1 2 .l1 V. N d e m. e ...u a u P n u u ?u .y W-

` 'wm/5.3853: www. W

(No Model.)

4 'Shetsj-Sheet 3.

Patented Nov. 12,1895.V

W/TN-ESSES.-

I 4 Sheets-Sheet 4.

(No Model.)

vPatented NOV..V 12.

'lim

ummm

l mwlmlmlmmmuu W/r/vEssEs: I i C v l IIIIIIIIIHHIIHIIIIHII'UHMEBHIIHI|UNITED STATES PATENT OFFICE.

ALFRED BOX, OF PHILADELPHIA, PENNSYLVANIA.

AUTOMATIC STOKER.

SPECIFICATION forming part of Letters Patent No. 549,868, dated November12, 1895. Application led March 13, 1895. Serial No. 541,610. (Nomodel.)

To all whom t may con/cern:

Beit known that I, ALFRED BOX, a citizen of the United States, residingat Philadelphia, in the county of Philadelphia and State ofPennsylvania, have invented certain new and useful Improvements inAutomatic Stokers; and I do hereby declare that the followingspeciiication, taken in connection with the accompanying drawings, is afull, clear, andeXact description of my improvements, vsuch as willenable those skilled in they art to make and use the same.

My invention consists, first, in providing independent adjustments forthe coal-feed and for the shaking grate-bars; second, providing thegrate-bars with roller-supports for rendering them more readily movable;third,

means for rendering the ash-pit door air-tight when using an artificialdraft, and fourth, improvements in the hollow water-back and side barsconnected therewith.

My invention also consists of certain features of construction forcarrying out the main points of my invention given above.

In order that my invention may be fully underst-ood, I will J'irstdescribe the same with reference to the accompanying drawings, andafterward particularly point out the novel features in the annexedclaims.

In said drawings, Figure 1 is a detail longitudinal sectional view ofasteam-boiler furnace, showing my improvements applied thereto. Fig. 2is a detail plan view of the same. Fig. 3 is an enlarged detail frontelevation of the right-hand side of the same. Fig. 4 is an enlargeddetail sectional view similar to Fig. 1. Fig. 5 is a detail perspectiveview of the adjustable connecting-rods which connect the shakinggrate-bars with the oscillating shaft. Fig. 6 is a sectional view takenon the line 6 6 of Fig. 4. Fig. 7 is a perspective view of one of thehollow side bars through which the water circulates. Figs. 8, 9, 10, 11,12, and 13 are enlarged details views of the mechanism for independentlyadjusting the coal-feed and the movement of the shaking grate-bars.

ISimilar numerals of reference indicate the same parts throughouttheseveral views.

The steam-boiler furnace shown in the drawings has a fire-wall 1 andmain ash-pit 2, a front plate 3, to which are hinged the ash-pit doors 4and draft-doors 5, and the smaller or supplemental ash-pit G behind thehollow water-back 7.

8 is a horizontally-hinged door controlling the passage of ashes fromthe supplemental ash-pit 6 to the main ash-pit 2, in which latter asuitable ash-pan may be provided, if desired. The door 8 is operatedthrough the rod 9, which passes through the sleeve 10, out through thefront plate 3, the outer end of the rod being omitted.

The water-back 7 is suitably supported at its ends in the masonry andcommunicates with the water-chambers 15. (Shown by dotted lines.)

16 are the hollow inclined bars, supported at each side of the lire-boxin the plane of the grate-bars and communicating with the water-back 7through the chambers 15. The con struction of these hollow side bars isclearly shown 'in Fig. 7. They may be supported by any suitable means inthe reebox, and suitable water connections may be made with a boiler toproperly circulate the water through them, the water-back, and theboiler.

20 are the open grate-bars,preferably formed with steps, as shown, withthe small openings 2l for the admission of air to support combustion.These grate-bars are substantially inverted-U shape incross-section-that is, without anybottom portionso as to allow theinterior of the grate-bars to be in free communication with the ash-pit,from which thev air to support the combustion is ordinarily supplied.The lower ends of the grate-bars 2O are formed with horizontal iiangedtracks 22, (shown in Fig. 1,) and are supported uponantifriction-rollers 23, which are journaled upon a rod 24, mountedinbrackets 25, formed on the front face of the water-back 7. In theupper horizontal portion 26 of each of the grate-bars is journaled anantifriction-roller 27, which projects just below the edge of thegrate-bar and rests on the horizontal baseplate 28 of the draft-flue 29.yThe base-plates 28 are extended slightly inward to form guidelugs 30for confining the grate-bars. The flues 29 are normally closed by thedoors 5.

It will be observed that the upper roller is inclosed by that portion ofthe grate-bar not used for fire-surface and is within the draftliuc, sothere will be no danger of its becom- IOO ing clogged with ashes. Thelower roller is also protected by being under the lower end of thegrate-bar.

Each one of the ash-doors et is provided with means for clamping ittightly to its seat .to render the ash-pit practically air-tight inorder that an artificial draft can be supplied through the iiues Q9 intothe open ends of the grate-bars. This means consists, preferably, of ashaft 35, journaled centrally in each door l, and having keyed to itsinner end a bar 36, and keyed to its outer end an operatin ghandle 37and an intermediate screw-threaded portion 3S, upon which operates aninternallythreaded hand-wheel 3). lVhen it is desired to securely clampthe door in closed position, the bar 3G is turned up into verticalposition to engage with the front plate 3 by means of a handle 37 andheld there while the handwheel 39 is revolved on the shaft $35, whichwill engage against the central boss -lO on the door and clamp the sametightly in place. To open the doors it is only necessary to loosen thehand-wheels and turn the bars 36 outof engagement with the frontplate 3,when it will be seen the door can be easily thrown open.

Vt'hen the natural draft is depended upon the doors are permitted to bemore or less open, the air passing up through the riser into the opengrate-bar.

l5 is a rock-shaft formed with a series of crank-arms to which arepivoted the upper sections i6 of the links which connect with thegrate-bars for imparting a shaking motion to them. The lower sections 47are journaled to the lugs 4S, formed on the grate-bars 20, the innercontiguous faces 49 of said sections 46 and 47 being serrated orgrooved, as shown,` and adjustable clamp-bolts 50 beingprovided toengage in the longitudinal slots 5l for clamping the links in thedesired adjusted position. By this means the connecting-links can belengthened or shortened to suit.

is a crank-arm keyed to the oscillating rock-shaft -l5 and projectingout through the opening 5G in the front plate 3. The crankarm 55 isformed with a slotted outer end 57, in which is adj ustably mounted aconnectingpin 58, having journaled to it a vertically-extendingconnecting-rod 59, which is operated for shaking the grates in a mannerpresently to bc explained.

G5 is the coal-hopper mounted upon the front plate 3 and having anopening 6G onto the grate-bars.

G7 is a pivoted plate supported below the opening GG and resting on theupper horizontal portions of the grate-bars for preventing the passageof air from the fine 29 above the grate-bars, and also to prevent anycoal from passing into the iiue from the fire.

J'ournaled in the hopper 65 is the poeketed feed-wheel G8, and supportedabove the feedwheel G8 is a plate G9, which is pivoted at 70 and restsupon flanged supports 7l. This plate is for the purpose of preventingthe improper feed of coal or air to the lire. The shaft 73 on thefeed-wheel G8 is journaled in the ends of the hopper (55, one end of thesame projecting beyond the hopper to be geared with the operatingmechanism.

I will now proceed to describe the independently-adjustable mechanismfor operating the coal-feed and the shaking grate-bars.

75 is a ratchet-wheel keyed to the shaft 7f3.' 76 is anotherratchet-wheel loosely j ourn aled upon the shaft 7 3 and adapted to moveindependently thereof.

77 is a crank-arm formed integral with. or connected tothe ratchet-wheel7U, and 7 S is a crank-pin mounted in the arm 77. The connecting-rod 59is journalcd to the crank-pin 7 8, so that the intermittent rotation ofthe ratchet-wheel 7 (i (by means soon. to be de scribed) willA cause therock-shaft 4-5 to oscillate slowly by intermittent steps for graduallyand intermittently n'ioving the grate-bars 2() independently of eachother.

8O is an armv journaled upon the shaft 7f3, between the ratchet-wheels75 and 7o, and 81 and S2 are pawls journaled upon each side of the arm8() on the pin 83.

Si is a small cylindrical casting projecting from each side of the arm8O directly under the pin S3, and S5 is a small spiral spring resting inthe cavity in each one of the projections S-l and bearing on theheels ofthe pawls Sl and 82 for holding them normally in operative position.

8G are small rollers journalcd on the forward ends of the pawls 8l andS2 for the pnrpose which will presently appear.

S7 is a connecting-rod journaled to the arm and ada-pted to be geared toany suitable operating mechanism which will impart an up-and-downmovement to it for operati ng the lpawl-and-ratchet mechanisms.

UO isa double dial secured to the end of the hopper (55 concentric tothe shaft 73.

Ul is a cam-track formed integral with a sleeve which journaled upon theshaft 73 and with an arm 92, having a concentric slot 03 and an index9i, which is adapted to register with the upper part of the scale 90.

is a clamping-bolt which works in the concentric slot 93 andis adaptedto hold the track 91 in any desired position, the position beingindicated by the index 9i and dial.

It will be observed that the cam-track .fll projects up from the shaft73 alongside of the ratchet-wheel 75, so as to come within the plane ofthe roller 8G. It will also be observed that this cam-track 91 projectssu flicently far from the shaft 7 3 to hold the pawl Sl out ofenga-gement with the ratchet-wheel 7G. This is for the purpose ofholding the pawl 8l out of working engagement with the ratchct-whecl 75for a portion of its stroke, so th at the amount of rotation of thefeed-wheel GS can be regnlated.

is a cam-track similar to the cam-track 91, it being formed with acentral sleeve by means of which it is jonrnaled upon the shaft TOO IIO

73, and an integral right-angled extension or arm 10l,which is formedwith a concentric slot 102 and the index 103, which registers with thelower portion of the scale 90. 104 is a clamping-bolt working in theslot 102 and adapted to secure the arm' 101 and its integral camtrack100 to any desired position. The purpose of this cam-track is the same.lt projects out from the shaft 73 alongside of the Iatchet-wheel 76 andengages the frictionwheel 86 of the pawl 82 for holding it out ofengagement with the ratchet-wheel 76 during a portion of its stroke. Byshifting the camtrack 100, each intermittent stroke imparted to theratchet-wheel 76 can be shortened or lengthened.

It will be observed that the cam-tracks 91 and 100 are readily adjustedby means of the arms 92 and 101, respectively, the clampingbolt beingfirst loosened.

In Fig. 11 the cam-tracks are shown in an adjusted position. In thisfigure the double dial 90 is done away with and two independent dials90a and 90b are substituted.

The operation of my automatic mechanical stoker will be clear from theabove.

Having thus fully described my invention, the following is what I claimas new therein and desire to secure by Letters Patent:

1. In a furnace, the combination of the water-back or support 7 ,thebrackets 25 proj ecting from the support 7, the rollers 23 journaled insaid brackets, the grate-bars 2O resting at their lower ends upon therollers 23 and having the rollers 27 j ournaled in their upperends,supports for the rollers at the upper ends of the grate-bars andmeans for reciprocating the grate-bars, substantially as set forth.

2. The combination, in afurnace, of the hollow grate-bars open on theirunder side, the ash pit, the draft iiue, doors to the draft flue and ashpit, andmeans for clamping the ash pit door firmly to its seatconsisting of a rod journaled in the door, and having a bar 36 andhandle 37 keyed to its inner and outer ends respectively, and the handwheel 39 working on a threaded portion of said rod, substantially as andfor the purpose set forth.

The combination of the grate-bars 20, the oscillating shaft 45, meansfor operating said shaft, and rods connecting the shaft with thegrate-bars; each of said connecting rods being formed of two sectionshaving grooved or serrated faces and provided with a clamping bolt forsecuring the sections together to form a rod of the desired length, asset forth.

4. The combination of the grate-bars, the oscillating shaft 45,connected with said gratebars, a crankarm extending from said shaft, aratchet wheel provided with a crank pin, a connecting rod connecting thecrank pin with the crank arm of the oscillating shaft, and means forintermittently operatin g the ratchet wheel, substantially as set forth.

5. The combination of a coal' chute of afurnace, a feed wheeljournaledin said coal chute and adapted to regulate the supply of coal to thefurnace, a ratchet wheel keyed to said shaft for operating the feedwheel, a second ratchet wheel loosely mounted upon said shaft, a seriesof reciprocating grate-bars, means for communicating motion from saidsecond ratchet-wheel to said grate-bars, an oscillating arm journaledupon said shaft between said ratchet wheels, two pivoted pawls journaledupon opposite sides of said oscillating arm and supported thereby inproper position to operate the two ratchet wheels, means for impartingmotion to said oscillating arm, and independently adjustable cam trackssupported concentrically to said shaft and adapted to hold said pawlsout of engagement with the ratchet-wheels for portions of their strokes,substantially as and for the purposes set forth.

6. The combination of a coal chute, a feed wheel journaled therein, aseries of reciprocating grate-bars, a ratchet wheel keyed to the shaftof the feed wheel and adapted to operate it, asecond ratchet-wheelloosely mounted upon the shaft of the feed wheel, means for impartingmotion from the second ratchetwheel to the reciprocating grate-bars, anoscillating arm journaled upon the shaft between the ratchet-wheels andcarrying a pair of operating pawls which are adapted to engage with saidratchet-wheels, means for imparting motion to the oscillating arm,independent cam tracks j ournaled upon the shaft and extendingconcentrically thereto and adapted to hold the pawls out of engagementwith their ratchet-wheels for portions of their strokes, operating armsextending from the cam tracks, an index on each operating arm, means forclamping the operating arms in any desired position, and scales withwhich the indexes on the operating arms register, substantially as andfor the purposes set forth.

ALFRED BOX. Witnesses:

WILLIAM ALFRED Box, CHRISTIAN AUGUST OPPENLANDER.

IOO

